The confirmed cause of death in nearly every North Atlantic Right Whale was a direct result of human-induced trauma, says a new scientific paper released this week.
Published in the journal Diseases of Aquatic Organisms, the paper reports on the causes of 70 North Atlantic right whale deaths over a 16 year time period (2003-2018). Of the 43 cases in which a cause of death was definitively determined, 90% died from trauma resulting from entanglement in line and vessel collisions.
An examination of studies dating back to 1970 showed that the increase in deaths from entanglement has increased from 21% to 51%. Lines wrap tight around the whale’s flippers, tail, head, or mouth, leading to lacerations or starvation from not being able to feed properly. Entanglement causes “immediate, traumatic drowning events in some cases and prolonged, painful deaths,” according to the International Fund for Animal Welfare (IFAW).
Approximately only 411 North Atlantic right whales remain today, many of which are found in the industrialized waters along the coastline between Florida and the Gulf of St. Lawrence in Eastern Canada. These busy waters increase the chances for whales to become entangled in debris or collide with vessels.
“Of all the causes identified, it is critical to emphasize that no adult or juvenile North Atlantic right whale deaths were a result of natural causes. Not one,” said Dr. Sarah Sharp of the IFAW. “This is clear evidence that these animals are unable to live full, productive lives because they are dying prematurely as the result of human activities. The high number of deaths documented over the past 16 years is not sustainable for this small population.”
However, Dr. Sharp, along with Tonya Wimmer, a Canadian investigator of the Marine Animal Response Society in Nova Scotia, believes that futher mortalities can be preventable is the United States and Canada work together to create “targeed and agrgressive mitigation measures.”
The paper suggests the following:
- Employing more effective gear modifications including ropeless fishing in both the US and Canada to minimize the chance of right whales encountering line in the ocean;
- Expanding vessel speed restrictions to include larger swaths of North Atlantic right whale habitat;
- Implementing dynamic management strategies (such as fisheries closures and mandatory speed restrictions) when right whales are seen in certain areas, which is especially important as right whale habitat use has become more unpredictable in recent years;
- Implementing coordinated gear marking to better monitor where and when whales get entangled and guide mitigation strategies; and
- Supporting continued and expanded efforts to survey offshore habitats for North Atlantic right whale carcasses to obtain more accurate mortality statistics and necropsy efforts to determine cause of death.
Whales and other sea creatures face man-made dangerous constantly. Chemical pollution in the ocean, specifically the leaking of PolyChlorinated Biphenyls (PCBs) into the water is a danger to whales and dolphins because their bodies are not made to manufacture the enzymes needed to breakdown dangerous chemicals like PCBs.
Oil spills, directly and indirectly, affect whale populations. Oil can enter into their blowholes or into their mouths, contaminating their bodies with oil toxins. Oil spills also tend to kill off smaller animals that dolphins and whales rely on for food.
Noise pollution is also a danger, as whales and dolphins rely on “listening” in the water. Noise pollution interrupts normal behavior and drives ocean animals away from areas important to their survival.
Of course, plastic and debris pollution may be the most harmful to whale and dolphin populations. It is estimated that 56% of whale and dolphin species have been recorded eating marine plastics that they’ve mistaken for food.